[R-sig-Geo] fit points in GWR

[Roger Bivand]

On Mon, 22 Jan 2007, Jason Kreitler wrote:

> All,
> 
> I am attempting to interpolate using the 'fit points' command within 
> GWR, but continue to run into problems. Can you recommend some example 
> code that utilizes the 'fit points' function? I haven't found an example 
> within the documentation.

GWR does not interpolate, it fits coefficients at fit points weighted by 
distances from the data points (where there are known values of the 
variables). The final example at the foot of the examples on the gwr() 
help page - example(gwr) - will run if you have packages maptools and 
gpclib installed (I think in the released version, YMMV), using a grid of 
SpatialPixels as fit.points=. It simply does gwr() for a regular grid of 
points within Georgia, after first merging the counties.

Hope this helps,

Roger

> 
> thanks much,
> jason
> 
> 

-- 
Roger Bivand
Economic Geography Section, Department of Economics, Norwegian School of
Economics and Business Administration, Helleveien 30, N-5045 Bergen,
Norway. voice: +47 55 95 93 55; fax +47 55 95 95 43
e-mail: Roger.Bivand at nhh.no